Credit: The Associated Press

In this photo taken with a mobile phone, Tuesday, May. 7, 2013, soldiers and journalist looks at bodies of prison officials killed by Islamic extremist during heavy fighting in Bama, Nigeria.

LAGOS, Nigeria — At first, the Islamic extremists in Nigeria's dusty northeast rode on the backs of motorcycles, firing on government officials and other perceived enemies with worn Kalashnikov assault rifles hidden beneath their flowing robes. Now, they come prepared for war.